A claviature having keyboard expression (action dynamics; Anschlagdynamik) is known. Such a claviature serves not only sending, to an electronic musical instrument, just ON-/OFF-information, that is triggered by pressing or releasing a key, but also providing information concerning a force or velocity exerted when pressing the key. Appropriate samplers (generators of sound; Klangerzeuger) use this information to vary a sound volume, but also a tone color (Klangcharakter) of the generated tone, dependent on the strength with which the key was actuated. Typically, in this manner, a sound of a piano is being simulated, in which tones being actuated in a strong manner are louder and have a more brilliant sound, because of the richer harmonics of the string being actuated more strongly. Thus, there is a need, also in the field of electronically playable musical instruments, to detect a dynamics of an actuation of a key.
Several different approaches are known, to derive information about a strength of an actuation with the help of sensors, that acquire a measurement signal, that is dependent on a manner of moving a key, for example by arrangements, wherein a magnet is moved within a coil, or the inductivity of a coil is modified by moving parts of a core, e.g. a ferrite core. It is also possible to use electrical sensors. In many of the known arrangements, the voltages measured in the described manner influence directly or indirectly the sampling.
These known methods require an involved implementation or are limited to specific genres due to limited possibilities of a generation of sound. Generally established are claviatures, in which the strength of an actuation is being output in an abstract parameter, the influence of which on the sound, in particular in the field of electronic instruments without any natural counterpart, can be used in most different kinds.
A standard for transmitting such information is the parameter “Velocity” within the MIDI data protocol. This value, usually being coded having a resolution of 7 bits, in the value interval of 0 to 127, maps slow key actuations to low number values, high velocities to high number values.
Known electronic keyboards acquire this value by measuring a time that was necessary for moving the key along a predetermined distance.
For this, in the easiest case, the key is provided with two switching contacts S1, S2, of which S1 is actuated at a position P1, after the key has been moved a small distance, starting from the rest position, and S2 is actuated at a position P2, when the key has been moved through a distance Δs.
A connected electronic monitors the keys and registrates an actuation of the switch S1. As soon as the actuation of the switch S1 has been detected, a time measurement commences. As soon as the switch S2 is actuated because of the proceeding movement of the key, the time measurement is stopped. Based on the elapsed time, the above mentioned velocity parameter is calculated and a tone request is generated, e.g., by sending the MIDI command “Note-On”. A short time Δt is translated into a high velocity value, a longer time Δt is translated into a smaller velocity value.
Alternatively or additionally to mechanical switches, optical sensors are arranged for detecting the different positions of the key. Also magnetically influenced switching elements, arranged in a stacked manner, are known. In principle, it is also possible to gain the information, as to when the key has moved from position P1 to position P2, using a linearly working sensor system.
Several approaches are known, to detect a larger number of positions of the key and, thus, achieving even finer differentiated time measurements for mapping the keyboard expression, by using refined arrangements of several optical sensors, e.g. by using fiber optical systems or mirror arrangements.
However, as a matter of principle, all these approaches suffer from a drawback: In order to enable a meaningful time measurement during the key movement, the key has to move a considerable distance, before a tone request can be triggered. In conventional systems, this distance is of circa 2 mm. If the distance is added, that the key has to travel, in order to reliably detect a deflection from the rest position, the so-called false touch (Leerreise, idle distance), triggering of a tone happens typically after an actuation of the key of about 4 mm.
Principally, claviatures having a velocity evaluation require a larger false touch distance than claviatures that do not exhibit keyboard expression. In particular in the case of organs, this is considered negative in regard of the playing properties, because known mechanical organ claviatures react already after a false touch distance of 1.5 to 2.0 mm, which is required by organists for playing rapidly.
For example, the document De 100 58 321 A1 is known. Disclosed herein are a contact control device and a contact control method, that can be applied to an electronic instrument. Herein, a key arrangement is disclosed, that generates contact data, that indicate a strength of a force of a key pressure. For achieving this, a key scanning arrangement is described, that measures a time, until a second key switch S2 is switched ON, subsequently to a first key switch S1 being switched ON upon an actuation of the key.
Thus, it is a task of the present invention, to provide an improved method and an improved device for detecting an actuation of a deflectable transmitter component, in particular in an electronically controllable musical instrument, in particular in an electronically controllable organ.